Cathode arc source

Abstract

The invention relates to a cathode arc process, comprising a target (3) having a target surface (3') with an active surface (3'') capable of evaporating material in a cathode arc process, a confinement section (4) surrounding the outer boundary of the target surface (3'), an anode (2) having electron receiving surfaces (2', 2'', 2''') surrounding at least one of the target (3) and the confinement section (4) in at least one of the target plane and the active surface in an axial distance, and a magnetic field line that is essentially parallel to at least an outer region of the target surface such that the magnetic field lines are parallel to the target surface or inclined thereto at an acute angle α. A cathodic arc evaporation apparatus comprising a magnetic guiding system configured to provide a magnetic field at a target surface, wherein the active surface (3'') is defined in a surface (3') area in which the magnetic field lines enter the target surface at an acute angle α≦45°, and a central axis Z or central plane Z', wherein the confinement (4) and the anode (2) are both formed with a closed geometry and both are electrically insulated from each other and from the target, and the minimum distance of the electron receiving surface (2', 2'', 2''') from the active surface (3'') is a radial distance Δr of the outer boundary of the target surface (3') to the inner boundary of the electron receiving surface 14 the outer boundary of the target surface (3') has a radial distance r1 from the center of the target, and the inner boundary of the electron receiving surface has a radial distance r4 from the center of the target at a radial distance Δr 14 and at least one of an axial distance h1 from the target surface (3') to an upper boundary of the containment section, or an axial distance h2 from the target surface (3') to a lower boundary of the electron receiving surface (2', 2'', 2''').

Description

Technical Field

[0001] The present invention relates to a cathode arc evaporation apparatus, a method for depositing a hard coating on a substrate, and a method for producing a coated substrate.

Background Art

[0002] Here, a cathode arc evaporation apparatus, also called an arc source or an arc evaporation source, is well known in the field of physical vapor deposition (PVD) as a main product for a number of various surface treatment and coating deposition processes, particularly in the field of tool coating and, to some extent, in the field of component coating. However, despite a wide range of applications, there are some inherent drawbacks in the state of the arc source, such as the high heat load transmitted from the surface of the arc source to the substrate and the high density of "particles", commonly called "droplets" or "macro particles", which can occur when the arc clogs (i.e., when the arc spot stays on a point on the target surface from which the target material evaporates for a sufficiently long time and the target material from the target surface melts without the possibility of proper evaporation and subsequent ionization), often leading to a molten pool that evaporates in an explosive manner to form so-called droplets having dimensions of up to several micrometers that can be seen on the substrate surface and within the coating, particularly on metal surfaces.

[0003] So far, only filtered arc sources seemed to solve both problems, but such arc sources are extremely expensive due to complex magnetic settings and lose many of the advantages of conventional arc sources that are highly productive in terms of coating speed and robust and easy to handle in processing.

[0004] There have been some promising developments with another source type, the so-called steered arc source, where the arc is confined to the surface by a static or dynamic magnetic field and is moved at a higher speed than a random arc within a specific path.

[0005] Krassnitzer et al. proposed in Patent Document 1 an arc source as shown in Fig. 5 to enable the production of a layer with a consistently high deposition rate and low surface roughness. The arc source includes a cathode (target), an anode, and magnetic means that enable magnetic field lines to connect from the target surface to the anode in a short connection. Thus, since the electron temperature of such a plasma is simply from about 0.3 eV to 1 eV, it is achieved that the behavior of the potential in front of the substrate is not distorted.

[0006] However, there is still a need for improvements particularly related to achieving a higher reduction in droplet formation in the coatings produced by a reactive cathode arc evaporation process, which does not require evaporating a target made of or containing a large proportion of chemical elements with a low melting point such as aluminum.

Prior Art Documents

Patent Documents

[0007]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0008] One object of the present invention is to provide a novel arc source that constitutes a solution for overcoming the above problems of arc sources according to the state of the art. In particular, the present invention can maintain the heat load (and thus the substrate temperature) on the surface of the substrate to be coated as low as possible, while at the same time enabling the coating of the substrate by using reactive cathode arc deposition technology so as to achieve a further reduction in the size and density of droplets in the coating.

Means for Solving the Problems

[0009] The object of the present invention is achieved by providing an arc source of the present invention as described below.

[0010] The arc source (cathodic arc evaporation device) according to the present invention has a target front surface of the material to be evaporated (hereinafter also simply referred to as the target surface) (the target surface to be evaporated is also referred to as the active surface in the description of the present invention, and the active surface is then the target surface from which the material is evaporated during the cathodic arc evaporation process), a target rear surface facing a target rear plate that is parallel to the target front surface but arranged on the side opposite to the target front surface, and a target side surface (hereinafter also referred to as the boundary or the boundary of the target) that connects the target front surface to the target rear surface, as a target serving as a cathode, and an electrically floating confinement member (hereinafter also referred to as the confinement member, or simply the confinement part or the electrically floating arc spot confinement part), which is preferably ring-shaped, but other configurations are also conceivable. For example, the confinement member may be square or rectangular. The confinement member is arranged adjacent to the target side surface, preferably surrounding or at least partially surrounding (but without direct contact). In particular, the confinement part is arranged to surround the outer boundary of the target surface (this means in particular that the confinement part is arranged to surround the surface of the boundary of the target adjacent to the target front surface). The electrically floating confinement member has an inner surface and an outer surface. The target side surface is closer to the inner surface of the confinement member than to the outer surface of the confinement member. An electrode serving as an anode having an inner surface to function as an electron receiving surface, and magnetic field generating means (hereinafter also referred to as a magnetic guiding system or simply magnetic means) configured to provide a magnetic field with magnetic field lines arranged in front of the front target surface. The inner surface of the confinement member is arranged between the target front surface and the electron receiving surface of the anode when considering the distance in a vertical plane with respect to the target front surface, and / or between the target side surface and the electron receiving surface of the anode when considering the distance in a parallel plane with respect to the target front surface.The magnetic field generating means is designed and adjusted to generate at least the following two magnetic field regions, namely a first region with magnetic field lines that emerge from the target front surface and end at the inner surface of the confinement member, and a second region with magnetic field lines that emerge from the target front surface and end at the electron receiving surface of the anode, such that when the arc source is operated within the vacuum chamber, it is possible to generate three plasma regions or plasma regions. The first plasma region (plasma region A or bright plasma region A or high electron temperature plasma region A) includes electrons that emerge from the target front surface and cross the magnetic field without access to the anode due to the magnetic field lines that end at the inner surface of the confinement member. In the second plasma region (plasma region B or dark plasma region B or low electron temperature plasma region B), electrons emerge from the target front surface and flow towards the anode due to the magnetic field lines that end at the electron receiving surface of the anode, thereby closing the primary circuit. In the third plasma region (plasma region C or dark plasma region C or low electron temperature plasma region C), there are no magnetic field lines that emerge from the front target surface and end at the inner surface of the confinement member, nor magnetic field lines that emerge from the front target surface and end at the electron receiving surface.

[0011] Thus, with the arc source of the present invention, surprisingly large improvements are achieved, and at the same time the following three advantages: namely, coating or plasma treatment of a substrate made of or provided with a temperature sensing material, which is beneficial for the formation of coating materials that require low temperatures for corresponding syntheses, leading to a low thermal load on the substrate, a low electron temperature in plasma regions B and C, and thus a low electron temperature of the plasma (usually plasma section C) surrounding the substrate to be plasma treated or coated, and a low ionization of the reaction gas in sections B and C, and thus a small amount of reaction gas ions (e.g., when nitrogen is used as the reaction gas, a small amount of gas ions N + and N 2+) and the reactive gas ions react with the material on the target front surface, causing a change in the state of the material on the target front surface (for example, when the material on the target front surface is a metal or a semimetal and nitrogen is used as the reactive gas, the gas ions N + and N 2+ react with the metal or semimetal on the target front surface to cause nitridation of the material on the target front surface such that smaller droplets and / or fewer droplets are generated (for example, when the target material is Ti or Al or AlTi and nitrogen is the reactive gas, during nitridation of the target front surface, a nitride layer of TiN or AlN or AlTiN is formed, leading to an increased steering rate of the arc spot advancing over the nitride layer, a decrease in the evaporation rate of the material on the target front surface, and a reduced emission of droplets, thereby depositing a coating on a substrate disposed in region C that exhibits a lower roughness (i.e., has a smoother surface)), which is accompanied by a significant reduction in the size and amount of droplets in the coating resulting from the increased plasma density of the reactive gas ions in plasma region A.

[0012] Definition The term cathode arc deposition apparatus is used as a synonym for the term arc source and, in this application example, is used in the same way as the term arc evaporation source.

[0013] The radial (r1,…rn) and axial (h1,…hn) distances and the terms higher and lower and their respective equivalents are used with reference to the concept of the arc source as shown in the figure unless stated otherwise. The terms inner and outer are used with reference to the axis or center line Z of the arc source, where Z defines the innermost position, unless stated otherwise. However, one skilled in the art will understand that the arc source can be placed at any position in the vacuum chamber, meaning the bottom, the side of the vacuum chamber, or overhead (not shown), and thus will interpret these terms with respect to the arc source as shown in the figure.

[0014] Surprisingly, it can be shown that the arc source of the present invention can also be used to deposit a chemical composition that is further away from the state of thermodynamic equilibrium than sources known in the state of the art, which is another object of the present invention.

[0015] More detailed and preferred embodiments of the cathode arc evaporation apparatus according to the present invention and of the method in which at least one cathode arc evaporation apparatus of the present invention is used will be described in more detail below.

[0016] In a preferred embodiment of the cathode arc evaporation apparatus according to the present invention, the apparatus comprises a target having a target surface (referred to above as the target front surface) with an active surface (referred to above as the surface to be evaporated) capable of evaporating the material within the cathode arc process, a confinement surrounding the outer boundary of the target surface, which may be a confinement body composed of a single piece body or several confinement elements, an anode having an electron receiving surface, the anode surrounding at least one of the target and the confinement at at least one of the axial distances in front of the target surface and the active surface, and a magnetic guiding system configured to provide a magnetic field with a target surface substantially parallel to at least the outer region of the target surface, which can comprise at least 50%, or 70%, or even more than 90% of the target surface, where being substantially parallel in this context means that the magnetic field lines are parallel to or inclined with respect to the target surface at an acute angle α ≤ 45°, or α ≤ 30°, or even α ≤ 25°, whereby the active surface region is defined and the effects such as an electron trap as described in detail below are described as increasing with a higher equilibrium of the magnetic field at and near the target surface, for example, in the region A also seen below, and a central axis Z for a circular arc source or a central plane Z' for a polygonal, for example rectangular arc source.

[0017] Both the confinement part and the anode are preferably formed in a closed geometry, such as a polygon like a ring or a rectangle, both are electrically insulated from each other and from the target, and the minimum distance from the active surface to the electron receiving surface is the following geometric parameter, i.e., the radial distance Δr from the outer boundary of the target surface to the inner boundary of the electron receiving surface 14 where the outer boundary of the target surface has a radial distance r1 from the middle of the target, the inner boundary of the electron receiving surface has a radial distance r4 from the middle of the target, and is defined by at least one of the axial distances h1 or h2 from the target surface to the upper boundary of the confinement part or the lower boundary of the electron receiving surface. This distance can be regarded as an axially effective distance with reference to the increase in the discharge voltage of the arc source

[0018] Thereby, a high plasma density can be achieved during the cathode arc process in front of the outer region of the target. Basically, due to the surface-parallel magnetic field and the floating potential formed by the insulated confinement part, most of the colliding electrons bounce back into the high-density plasma, where they are captured and made to move in a circular motion similar to a race track of a sputtering target. Only when the electrons escape on the outermost magnetic field line that further enters the confinement part at the axial distance h1 and the radial r4, the electrons are driven towards the anode, which is normally at ground potential, by a further significant magnetic field in the region between the electron receiving surface and the target surface, and are neutralized there

[0019] Thereby, the basically parallel magnetic field can extend from the target active surface up to at least one axial distance (h1 or h2) of the confinement part or the electron receiving surface, or can extend to a height of at least 5 to 20 mm on the target surface

[0020] In any embodiment of the present invention, an active upper region A including a basically parallel magnetic field is provided, with a magnetic flux density B AThe intensity can be set from 20 to 500 gauss or more, for example, about 40 to 60 gauss at the median diameter of the target surface, and about 500 gauss or more at a few millimeters of the close proximity part, the strong magnetic center limiter when utilized. Region A is laterally limited by a confinement part that also limits the outer boundary or diameter of the target active surface. With respect to the center of the target, region A can be delimited either by an inactive surface region of the target where magnetic field lines enter the target surface at an angle > 45°, or by a center limiter having the properties of a magnetic center yoke as described below. Axially from the target, region A is delimited by the last magnetic field line that enters further into the confinement part, which is, for example, its lowest or innermost boundary, right before the next magnetic field line that enters the electron receiving surface.

[0021] As shown below, the confinement part can be made of a magnetic or non-magnetic material, such as magnetic steel, or non-magnetic steel, ceramic or other materials that can withstand high thermal loads near the target active surface, for use with respect to the center limiter.

[0022] The radial distance Δr between the outer diameter of the target active surface and the inner diameter of the electron receiving surface 14 is from 5 to 30 mm, for example 20 ± 5 mm. This distance can be regarded as the effective radial distance with reference to the increase in the discharge voltage of the arc source.

[0023] The radial distance r1 from the center of the device to the outer boundary of the target surface is from 80 to 220 mm, for example 15 ± 5 mm.

[0024] The axial distance (h1 or h2) is from 0 to 20 mm, for example 15 ± 5 mm.

[0025] The maximum axial distance h3 from the target surface to the electrical receiving surface can be 10 ≦ h3 ≦ 50.

[0026] The magnetic guidance system can comprise at least a central magnet having a pole arranged in front of the center of the rear surface of the target and axially aligned therewith, and a circumferential ring magnet having inter-poles in or below the target plane. The ring magnet is supposed to surround at least a part of the central magnet and the target when overlapping, for example, when the inner diameter of the ring magnet is smaller than the outer diameter of the target, or otherwise preferably surround the target as a whole.

[0027] At least one of the central magnet and the ring magnet can potentially be an electromagnet or a permanent magnet. When permanent magnets are used, each magnet can be arranged, for example, in a circular arrangement with the same poles as the ring magnet, which can be made from a single piece or by the arrangement of permanent magnets.

[0028] The magnetic axis of the ring magnet can be inclined away from the central axis Z or the plane Z' in the upward direction. The axis of the central magnet is usually in the center and parallel to the axis Z.

[0029] In another embodiment of the present invention, the ring magnet may comprise two electromagnetic coils C2 and C3, and the diameter of C3 is larger than the diameter of C2. Such coils can have separate coil yokes or a common coil yoke as shown below and can be mechanically or simply magnetically connected to the circumferential yoke.

[0030] The magnetic guidance system of any embodiment can further comprise a circumferential yoke surrounding the ring magnet, the target, and the anode. The circumferential yoke is made of a magnetizable material, for example, iron, martensitic steel, or the like.

[0031] In another embodiment, the magnetic guidance system can further comprise a central limiter arranged inside or around the center of the target surface. The central limiter is electrically insulated from the target and has a Curie temperature T C >500 °C, T C >600 °C, or further T CIt is made of a magnetic material having a temperature >650°C. Each material may be, for example, a pure iron structural steel having a low carbon content, or a ferritic corrosion-resistant steel having a Cr content higher than 10.5 mass%. Such a central limiter can have a width or diameter of 20 to 50 mm, for example 30 to 40 mm, and can be in the shape of a disc or a ring with respect to a circular target.

[0032] For example, when at least one of the confinement part and the anode protrudes from the target surface, the central limiter can protrude 0 to 20 mm, or 5 to 20 mm, on the target surface or with respect to the axial distances h1 or h2.

[0033] In another way, the central limiter can be in the same plane as the target surface. For example, when at least one of the confinement part and the anode protrudes from the target surface, the central limiter can protrude 5 to 20 mm on the target surface or with respect to the axial distances h1 or h2.

[0034] In any embodiment of the present invention, the confinement part can be made of a non-magnetic material.

[0035] In another preferred embodiment of the present invention, the minimum distance from the active surface to the electron receiving surface is defined by the radial distance Δr 14 and the axial distances h1 or h2.

[0036] The present invention also targets a vacuum chamber equipped with a cathode arc deposition device as described above.

[0037] Furthermore, the present invention targets a method for depositing a coating on a substrate in a vacuum chamber by using a cathode arc evaporation apparatus as described above, wherein the electron trap establishes, in region A, a substantially parallel magnetic field with magnetic field lines entering the target surface at an acute angle α≦45° in at least the outer region of the target surface by applying a magnetic guiding system, thereby forming an active surface. The method further includes igniting and maintaining a cathode arc discharge on the active surface, whereby the arc spot is steered by the parallel component of the radial magnetic field, and region A is laterally delimited by a confinement at a floating potential surrounding the target. Region A can be delimited by either the inactive surface region of the target or the central limiter, with respect to the center of the target. Axially from the target, region A can be delimited by the last magnetic field line 9 entering the confinement at its upper boundary.

[0038] The method can further include the formation of region B formed over region A up to a distance h3, given by the maximum axial distance of the electron receiving surface from the target surface. More precisely, region B, where electrons that may escape from region A can further advance therein in a circular path by the current magnetic field towards the anode, starts at its lowest or innermost boundary following immediately after magnetic field line 9 that constitutes the last magnetic field line that enters the confinement section at its upper or outermost boundary, for example, by magnetic field line 8’ entering the electron receiving surface, and is delimited in the upward direction at its highest or outermost boundary, for example, by the last magnetic field line 8 entering the electron receiving surface. Both magnetic field lines originate from the central magnet or central limiter. It is clear that the average magnetic field strength of region B is smaller than that of region A. However, the magnetic field strength and magnetic flux within region B are basically higher than zero, and for example, in order to efficiently drive electrons that may escape from the electron trap in region A towards the anode that delimits region B in the lateral direction, it is preferable that a magnetic flux from 5 to 20 gauss can be added. At the anode, the electrons are discharged, exit the plasma, and thus are no longer available for another ionization or collision process that heats the process gas or other parts of the vacuum chamber. Therefore, the heat load at the anode is basically higher than that of a conventional arc source that can be managed by direct or indirect water cooling of the anode and the use of a high heat conduction anode material such as copper.

[0039] Here, an anode with two or more components can be used, for example, an anode having an inner anode ring extension that fits tightly into the outer water-cooled anode body, and the inner ring can be easily removed or replaced for maintenance purposes. At the same time, the heat load on the substrate can be basically reduced. On the one hand, a strong bright arc plasma in which most of the arriving reactive molecules such as nitrogen or oxygen containing process gas are immediately ionized is confined to region A and does not expand into the vacuum chamber. Such a bright plasma can have a similar lateral distribution as can be seen from the so-called race track of the sputter target. Thereby, the target surface can be completely reacted, for example, nitriding, oxidizing, or both nitriding and oxidizing are performed when nitrogen and oxygen containing process gas are used simultaneously, and due to the high melting point of such compounds, the undesirable formation of a liquid metal pool and its "explosive" evaporation in the arc track can be efficiently suppressed, otherwise leading to a high density for distributing droplets on the surface of the coated substrate. On the other hand, the heat of the electrons is efficiently absorbed by the water-cooled anode. An inspection that measures the temperature difference of the cooling water for the anode and the target shows that when the arc evaporation device of the present invention is used, more than 80%, more than 90%, or even more than 95% of the process energy supplied by the arc source can be dissipated by the respective cooling circuits of the target and the anode. However, in a conventional arc source, only 50% to 55% of the heat is dissipated by the respective cooling circuits, which means that the heat load on the substrate is reduced to about 90%, and the substrate temperature between 150°C and 350°C, especially between 150°C and 300°C, can be achieved without the need to cool the substrate separately.

[0040] The method can further comprise a region C formed over regions A and B between the arc source and the surface of the substrate to be coated with reference to the deposition process within the vacuum chamber, the magnetic field being very low or zero, and the atmosphere containing at least one of reactive gas molecules, and positively ionized metal ions and positively ionized reactive metal ions. Optionally, the atmosphere can further contain at least one of inert gas molecules. The proportion of ionized reactive gas molecules within region C is very low or negligible with respect to the high ionization within region A. Thereby, the reactive gas molecules, and the positively ionized metal ions and / or the positively ionized and reacted metal ions are important and, as an example, can form at least 80%, such as 95%, or even 99% or more of the reactive atmosphere in which the substrate is submerged.

[0041] With the help of a magnetic guiding system and a floating confinement section, both acting like a plasma resistance, which can be adjusted by the magnetic field strength and the distances r4, h1 and / or h2, the discharge voltage of the arc source can be raised to be between 20 V and 50 V, between 25 V and 40 V, or between 30 V and 35 V to generate strong ionization of the operating gas near the target surface. This is basically above the discharge voltage of known arc sources, which are typically driven at a discharge voltage of up to 10 V to 20 V.

[0042] To summarize by use of the arc source of the present invention, the deposition process can be designed with a high plasma density confined in region A directly above the surface of the substrate, thereby providing a high reaction of the target surface with the reactive process gas. In region B, the electrons can be efficiently removed before exiting towards the free space within the vacuum chamber. At the same time, the reactive gas ions coming from region A can recombine in region B and / or at the anode surface. Thus, region C basically has no free electrons, i.e., electrons not bound to molecules or metal ions, and the reactive gas ion concentration is low or near zero. Referring to the particles to which the load is applied, basically relatively heavy metal ions (Men+ ) and metal compound ions, e.g., MeM n+ and / or MeO n+ Many of these can be detected in region C, where deposition material is provided together with metal ions or reactive gas molecules that can react with the incoming metal ions or metals containing ions on the substrate surface. Other species with additional loads as electrons and nitrogen ions are mostly confined at high density in region A near the target surface and in regions A and B.

[0043] Such plasma modification renders the source highly suitable for the low-temperature deposition of hard coatings and processes it to deposit compound compositions from a state of thermodynamic equilibrium. As an example, compounds of AlMeN, AlMeO or AlMeNO with different stoichiometric compositions can be deposited, where Me represents one or more metals of transition metal groups IV, V or VI (US: groups 4b, 5b, 6b) including Ti, V, Cr, Zr, Nb, Mo, Hf, Ta and W. As an example of such a coating, the deposition of cubic TiAlN that can be deposited in a pure cubic phase at concentrations of 70% and 80% of Al should be described. The percentages are given with reference to the metal content of the compound, i.e., (Al 0.7 Ti 0.3 )N or (Al 0.8 Ti 0.2 )N. The reactive elements may be in stoichiometric, sub- or over-stoichiometric concentrations with reference to the metal composition.

[0044] The present invention will now be further illustrated with reference to the drawings.

Brief Description of the Drawings

[0045]

Figure 1

Figure 2

Figure 3

Figure 4

Embodiments for Carrying Out the Invention

[0046] FIG. 1 shows in the most schematic and simplified way an embodiment of an arc source I according to the present invention, a planar target 3 with a radial width or diameter r1 thereby, and respective confinement parts 4 surrounding the target, and an anode 2 surrounding both the target and the confinement part. The target can be of polygonal shape, for example rectangular, or circular shape, and Z thus defines the central plane or the axis of the target. In the following, for ease of understanding, it is called a circular and ring-shaped target with reference to FIGS. 3 and 4, but such dimensions can be easily converted to other planar targets, i.e., targets having flat surfaces to be evaporated of different shapes included in the present invention. Also with reference to FIGS. 3 and 4, due to the nested configuration of the arc source from FIG. 1, the inner diameter r2 of the confinement part is usually larger than the outer diameter r1 of the target 3, or for example, when the confinement part protrudes the target surface by several millimeters (not shown) and is configured to form an arc extinguishing distance upward instead of laterally as shown in the figure, it is at least larger than the outer diameter of the target active surface 3'. Such a distance, here r2~r1, should be in the range of 1.5 to 3 mm in order to ensure that an electric arc advancing on the surface of the target slowly advances into the gap formed between the target and the confinement part and cannot expand to the confinement surface. At the same time, the generation of unwanted parasitic plasma in the gap can be avoided. A similar distance can be selected for the distance r4~r3 between the outer diameter r3 of the confinement part 4 and the inner diameter r4 of the anode, or for the respective axial distances h2~h1 of the confinement part 4 to the anode 3 as shown in FIG. 2, or for a modified form of the anode shape 2''' shown by the dashed line in FIG. 1. Thereby, electrical contact and unwanted plasma formation between the electrically insulated confinement part and the anode can be effectively avoided.

[0047] In the region where the magnetic field lines enter the target surface, i.e., the so-called active surface 3', at an acute angle of α ≤ 45°, the electric arc can be ignited and circularly steered by the radial magnetic field. Thereby, a strongly glowing plasma 10 (hereinafter also referred to as the reactive gas plasma) can be formed, which can effectively dissociate reactive gas molecules such as nitrogen, oxygen, or carbon-containing gases entering this region into their atomic and respective ionic components, and thereby assist in reacting the metal target active surface or metal ions or clusters leaving the arc advancing on the surface. Thereby, most of the possible reactive plasma processes, such as nitriding, oxidizing, carbonizing, or processes with mixed reactive gases, are likely to occur on or near the target surface in region A, which is in the region between the last magnetic field line 9 entering the confinement and the target surface 3, particularly the target active surface 3' formed in the outer surface region in the embodiments shown in FIGS. 1 and 2. Region A can also be regarded as an electron trap assuming that electrons are reflected from the confinement wall surface and can escape from the plasma only when reaching region B between magnetic field lines 9, 8' and magnetic field line 8, where magnetic field line 8 enters the electron receiving surface at its highest or outermost boundary, and as shown in FIG. 2, magnetic field line 8' enters the electron receiving surface at its lowest or innermost boundary just above magnetic field line 9. In region B, the electrons are neutralized at the anode 2. The electron receiving surfaces 2', 2'', 2''' of the anode 2 can be formed to be geometrically different, for example, simply cylindrical 2', and / or, for example, inclined with respect to the axis Z as shown by the dashed line 2'', or protruding above at least a part of the confinement 4 as shown by the dashed line 2''' in FIG. 1. The anode further comprises an anode cooling channel 6' (not shown in the figure) that can be connected to a dedicated or common, for example, water-based cooling line.

[0048] Similar to the electron-receiving surface defined by the inner and / or upper surface of the anode, the inner and / or upper surface of the confinement part 4 can be geometrically different, for example, simply cylindrical 4', and / or, for example, at least partially, inclined differently with respect to the axis Z as shown by the dashed line 4'', or protrude the target surface as shown by the dashed line 4'''.

[0049] All arc sources of the present invention further comprise a magnetic guiding system configured to provide a magnetic field in front of at least the outer region of the target surface, similar to the embodiments shown in FIGS. 1 and 2, or over the entire target surface, similar to the embodiments shown in FIGS. 3 and 4. By "basically parallel" is meant here that the magnetic field lines enter the target active surface at a more acute angle α ≤ 45°, or α ≤ 30° or α ≤ 25°. Such a magnetic guiding system, as exemplified in FIGS. 3 and 5, can also be used in any other embodiment, for example, in Embodiments 1 and 2 of the arc source of the present invention, and usually comprises a central magnet 14 and a ring magnet 15, the latter surrounding the central magnet and, optionally, at least hypothetically the target 3. The ferromagnetic yoke 17 at ground potential can also, in any embodiment, further contribute to forming a magnetic field, for example, by helping to limit the radial expansion of the magnetic field lines.

[0050] FIG. 2 shows an embodiment of the present invention of an arc source II with a cylindrical anode 2 arranged at the upper part of a cylindrical confinement part, both having the same inner diameter. In this case, basically only the distance h2 contributes to the increase in the discharge voltage of the arc source, while in any other embodiment as shown in other figures, the axial distances h1 or h2 and the radial distances r5 to r2 contribute. Since the latter distance is reduced to the gap between the target and the confinement part, it can be almost ignored in FIG. 2.

[0051] In another embodiment (not shown), the confinement portion is formed as a ring surrounding the target at the target surface level, and the anode is formed as a ring surrounding both at the same level. In this case, basically, when the inner confinement surfaces 4', 4'', 4''' and the inner electron receiving surface are arranged at the same level as the target surface 3, only the radial distances r4 to r1 contribute to the increase in the discharge voltage of the arc source when they are completely exchanged with the respective upper confinement portions and the anode surface.

[0052] Figure 3 shows an arc source III similar to that of Figure 1 having a basic magnetic guiding system with a central permanent magnet 14 having its magnetic axis Mc collinear with the central axis Z, and the magnetic axis M of the ring magnet 15 r is inclined away from the central axis Z or the plane Z in the upward direction. The inclination angle of the magnetic axis M with respect to the central axis Z r is between 0 and 45°, for example, between 5 and 30° depending on the respective situations. Here also, the magnetic division lines are affected and are inclined respectively, so that a flatter or more parallel path of the magnetic lines of force on the target surface can be reached. In this context, the division line is, on the one hand, a plane between the magnetic lines of force proceeding from one pole, here the S pole of the ring magnet, to the opposite pole, here the N pole of the central magnet, and on the other hand, the magnetic lines of force proceeding from one pole of the ring magnet to the opposite pole of the same ring magnet. Those skilled in the art will understand that the magnetic poles can be interchanged. For example, a strong magnetic peripheral yoke 17 with an anode potential which is normally at ground potential can be used to make the magnetic lines of force more parallel on the target surface and to shield the magnetic field radially outside the peripheral yoke surrounding the entire arc source in the lateral direction. In Figure 3, the central magnet 3 is arranged directly below the target rear plate 12 provided with a target cooling channel which can be connected to a dedicated or common, for example, water-based cooling line (not shown in the figure). Alternatively, the central magnet can also be arranged within the rear plate 12, for example, within the cooling channel 13.

[0053] Furthermore, an arc source of type III or IV as shown below in Fig. 4 is provided with a strong magnetic center limiter 16 at or in the center of the target 3 with an electrically floating potential. Thus, the yoke 16 is mounted on an insulating device 19 of an electrically insulating and heat-resistant material such as ceramic, similar to the floating-mounted confinement part 4 mounted with the help of at least one electrical insulating device 20. The gap between the center limiter 16 and the target should be of the dimensions as described above for the confinement part 4, in the range from 1.5 to 3 mm.

[0054] With the help of the center limiter 16, the magnetic field lines f symbolically shown m can be formed substantially parallel to the entire target surface 3'. Thereby, the target active surface 3'' can also extend over the entire surface 3', in this case, the surface ring. Due to the high heat load in the middle of the target, any center limiter 16 in any embodiment should preferably be made of a magnetic material having a high Curie temperature T C of 600 °C or higher. The magnetic permeability μ r of such a material should be higher than at least 100, or even higher than 500, and the saturation magnetization should be higher than 0.3 tesla, further higher than 0.5 tesla. In particular, when magnetic arc steering requires a dynamic magnetic field, such a material has a low residual magnetism B r and, for example, when the magnetic coil is variable, for example driven by a pulsed current, the respective coercive force H C should be lower than 200 A / m, or equivalent, or lower than 50 A / m.

[0055] Examples of such materials are pure iron such as ARMCO® iron having a T C of 766 °C, structural steel with a low carbon content such as S235 or S355 steel having a T C of about 768 °C, or having a T C of 671 °C with a low Si concentration of 0.30 to 0.70 mass%, or having a T CIt is a ferritic corrosion-resistant steel having a chromium content higher than 10.5%, for example, from 17.25 to 18.25, in accordance with ASTM A838-02(2007). The magnetic properties of the circumferential yoke 17 are the same, but when this yoke is away from the hot target surface, austenitic steel and other less expensive magnetic materials with their respective properties can be used at a much lower Curie temperature.

[0056] Similar to FIG. 3, an arc source equipped with a strong magnetic center limiter is shown in FIG. 4, where it is in the simplest schematic vacuum chamber 1 having a substrate 7 mounted on the arc source IV. Contrary to the type III arc source of FIG. 3 that uses permanent magnets, the magnetic guiding system of the type IV arc source utilizes electromagnets C1, C2, C3. The magnet 14 is realized by the electromagnetic coil C1 with a central coil yoke 18, and the ring magnet 15 is realized by the coils C2 and C3 and the outer coil yoke 21.

[0057] FIG. 4 shows the realized industrial arrangement of the arc source type IV of the present invention with an electromagnetic guiding system. The magnetic field lines are the actual magnetic field lines that can be generated in such a system as the overlap of the magnetic fields H C1 , H C2 and H C3 . The central magnet 14 is provided with the electromagnetic coil C1 and the central coil yoke 18, and the ring magnet 15 is provided with the electromagnetic coils C2 and C3, and the outer coil yoke 21. To generate such a magnetic field, the magnetic axis M r and the respective dividing lines of the ring magnet 15 are inclined away from the central axis Z in the upward direction by applying a higher current to C2 than to C3, where I C2 > I C3 . In another way, such an effect can also be achieved by different turns N, for example, N C2 > N C3It can be generated by supplying the same current to the coil. The anode is a two-part anode having an anode body 25 with a cooling channel 6 and an inner ring-shaped extension 26. The vacuum seal 22 seals the vacuum chamber 1 against the atmosphere and water from the cooling circuits 6, 13. The substrate 7 can be attached to a substrate support (not shown) in a known manner, for example, by rotating. Regions A, B, and C are substantially separated from each other by magnetic field lines 8 and 9 as shown. With such a configuration, a dilute arc source having an outer diameter of 220 mm can be realized with a target diameter of 130 mm and a strong magnetic central limiter of 36 mm. The total height from the back side of the target 3 to the upper boundary of the electron receiving surface 2 is about 53 mm.

[0058] In an industrial environment using an Oerlikon batch coating apparatus that provides a coating height of 1000 mm, up to 24 type IV arc sources can be installed in 4 rows, each row having 6 arc sources per meter on top of each other, thereby depositing hard coatings of the AlMeN and AlMeNO types on different substrates at high speed and with a high aluminum content. Pure cubic phase compounds can be deposited with an aluminum content ranging from zero to 85%, particularly at a high aluminum concentration between 70 and 85%, in combination with at least one of, for example, Ti and Cr. The chamber diameter of such an apparatus is 1000 mm and it has a carousel with a diameter of 700 mm and a chamber height of 2000 mm. Among the substrates attached by 1, 2, and 3 rotations, the substrate closest to the target distance is about 300 mm. Similar tests have been conducted on the applicant's present invention and another industrially available coating system of an inventive type. Thereby, the industrial applicability can be examined for the following chamber dimensions: a chamber diameter of 500 - 1200 mm, a carousel diameter of 300 - 900 mm, a chamber height of 1000 - 2000 mm, and a usable coating height of 500 - 1500 mm.

[0059] The properties and geometric data of specific core components of the arc source of the present invention are given below.

[0060] The targets can be cooled either directly or via a bonded backplate, depending on their respective material strengths. Both types can be mounted on a water-cooled cathode electrode. Circular diameter D T satisfies 60mm ≦ D T = 2r1 ≦ 200mm, 100mm ≦ D T = 2r1 ≦ 150mm. The material can be any solid material compatible with arc evaporation.

[0061] The confinement part is mounted and insulated between the target and the anode, thereby inducing a potential between the cathode target potential and the positive or grounded anode potential during the cathode arc process. Inner diameter D CI satisfies 95 ≦ D CI = 2xr2 ≦ 155mm, for example 132mm. The thickness t in the radial direction (r3~r2) CR satisfies 10 ≦ t CR ≦ 30mm, for example 148mm. The thickness t CR merely refers to the surface area of the confinement ring that can be exposed to the arc plasma. It should be noted that the total thickness extension of the confinement ring may be larger depending on the configuration mechanism of a specific arc source, for example, when the anode extension overlaps, thereby protecting the outer part of the confinement ring against interaction with the plasma. The distance h1 from the active surface to the upper surface or top of the confinement ring (in the planar embodiment) satisfies 0 ≦ h1 ≦ 20, and in the preferred range for the cylindrical and combined embodiments, for example, FIGS. 1 to 4, 10 ≦ h1 ≦ 30, for example 15 ≦ h1 ≦ 25. The radial distance of the confinement ring in the region where at least the confinement ring surrounds the target within the target plane is typically defined by the distance d D = r3 - r2 = r4 - r5 = h2 - h1, for which 1.5mm ≦ d D≤3 mm is effective, so that this distance is compatible with the dark space distance at normal process pressure, preventing the expansion of the arc spot with respect to the confinement part and the parasitic plasma between the components of the source. As materials, not only ferromagnetic materials such as iron and carbon steel, but also non-magnetic metals having a melting point high enough to withstand the high heat load of adjacent arc discharges, such as stainless steel, can be mentioned.

[0062] The internally water-cooled anode is set at a positive potential or ground potential. The inner diameter D that defines the inner diameter of the electron receiving surface AI satisfies 80 mm ≤ D AI = 2xr4 ≤ 220 mm, 120 mm ≤ D AI = 2xr4 ≤ 170 mm or satisfies about 150 mm. The radial thickness t AR satisfies 10 ≤ t AR ≤ 40 mm. The distance h2 from the active surface to the upper part of the electron receiving surface or the confinement ring (for example, in the planar embodiment) satisfies 0 ≤ h1 ≤ 50, and in the preferred range for the cylindrical and combined embodiments, it satisfies 10 ≤ h1 ≤ 35. h2 may be the same as h1 when the confinement part is nested within the anode, for example, when the anode has electron receiving surfaces 2', 2'' according to FIGS. 1 and 3. The material may be copper, carbon steel or stainless steel.

[0063] As the total geometry of the cathode assembly, it satisfies a diameter in the range of 150 mm ≤ DSource ≤ (for example, in the cylindrical modification) 290 mm, or 180 mm ≤ DSource ≤ 260 mm (for example, in the planar modification).

[0064] The magnetic guiding system for generating a magnetic field has high parallel components at least near the upper part of the outer region of the target active surface. The means is provided in front of the rear surface of the target, for example, on the back plate of the cathode electrode, and includes a guiding system that is electrically insulated from the electrode. Optionally, the guiding system can be attached (at a floating potential) to the center of the target surface and / or the circumferential yoke and supported by a strongly magnetic central limiter that is electrically insulated.

[0065] In the strong magnetic center limiter, the circular diameter D Y satisfies 15 mm ≤ D Y ≤ 50 mm, and is, for example, 36 mm. Examples of materials include pure iron, construction steel with a low carbon content, and ferritic corrosion-resistant steel. For details, please refer to the above.

[0066] The magnetic field that can be set by the source of the present invention should be basically parallel to and close to the target active surface, at least with respect to the outer region of the target active surface. The formation of the three sections (A, B, C) during the possible cathode arc process in terms of magnetic flux density is such that B A > B B > B C is satisfied. For details, please refer to the above.

[0067] The arc source supply may be, for example, a DC supply that carries a discharge current of 10 to 200 A, for example, 40 to 120 A per source. Alternatively, a DC supply with a pulsed arc supply or a multi-layer pulsed supply can be used.

[0068] Contrary to the state-of-the-art sources driven at a discharge voltage between 12 and 20 V, the source of the present invention can be driven at a discharge voltage between 20 and 50 V, for example, between 25 and 40 V or between 30 and 35 V, due to the higher resistance of electron capture that can be formed in region A, for example, by the geometric shape, material, and magnetic means of the present arc source.

[0069] Finally, the combinations of mechanisms described in one embodiment, example, or type of the present invention can be combined with any other embodiment, example, or type of the present invention, as long as there is no contradiction.

[0070] Specifically, the present application relates to the front surface of the target of the material to be evaporated, i.e., the target active surface the back surface of the target that is parallel to the front surface of the target but faces the target back plate arranged on the opposite side with respect to the front surface of the target, and The target side surface that connects the target front surface to the target rear surface a target as a cathode having the same, and electrically floating confinement part which is disposed adjacent to, preferably surrounding or at least partially surrounding the target side surface, and has an inner surface and an outer surface, wherein the target side surface is closer to the inner surface of the confinement part than to the outer surface of the confinement part, an electrode as an anode having an inner surface that functions as an electron receiving surface, and a magnetic guiding system configured to provide a magnetic field with magnetic field lines located in front of the target front surface, relating to a cathode arc evaporation apparatus comprising the same, the inner surface of the confinement part is disposed between the target front surface and the electron receiving surface of the anode when considering the distance in a vertical plane with respect to the target front surface, and / or is disposed between the target side surface and the electron receiving surface of the anode when considering the distance in a plane parallel to the target front surface, the magnetic guiding system is designed and adjusted to generate at least the following two magnetic field regions, namely a first region with magnetic field lines disposed in front of the target front surface that emerge from the target front surface and end at the inner surface of the confinement member, and a second region with magnetic field lines disposed in front of the target front surface that emerge from the target front surface and end at the electron receiving surface of the anode.

[0071] Preferably, the apparatus comprises an electrically floating strong magnetic center limiter (16) for changing the trajectory of the magnetic field lines emerging from the target front surface to be substantially parallel to the plane of the target front surface.

[0072] The present invention also relates to a method for operating the apparatus of the present invention, during operation of the apparatus in a vacuum chamber, three plasma regions or plasma regions are generated, the first plasma region comprises electrons that cross the magnetic field without access to the anode by magnetic field lines emerging from the target front surface and ending at the inner surface of the confinement member, In the second plasma region, electrons exit from the front surface of the target and are flowed to the anode by magnetic field lines that start from the front surface of the target and end at the electron receiving surface of the anode. In the third plasma region, there are neither magnetic field lines that start from the front surface of the target and end at the inner surface of the confinement member nor magnetic field lines that start from the front surface of the target and end at the electron receiving surface.

[0073] The electron temperature by performing the above method is preferably between 1 eV and 5 eV in the first plasma region and between 0.3 eV and 1 eV in the second and third plasma regions.

[0074] The method of the present invention is at least one step in which a reaction gas is guided into a vacuum chamber and the apparatus is operated while the reaction gas is being guided into the vacuum chamber, wherein the first plasma region contains more reaction gas ions than the second and third plasma regions, and thus, the reaction gas ion density in the first plasma region is higher than the reaction gas ion density in the second and third plasma regions.

[0075] In a preferred embodiment of the method, the target or at least the front surface of the target is made of a metal material, and the reaction gas reacts with the metal material from the target to form a layer containing elements from the reaction gas and elements from the metal material.

[0076] According to a further preferred embodiment, the target consists of or contains Ti or Al or Al and Ti, and the reaction gas is nitrogen or contains nitrogen, whereby the layer obtained from the reaction of the reaction gas with the metal material from the target is a nitride layer consisting of or containing TiN or AlN or AlTiN, respectively.

[0077] According to a more preferred embodiment, taking x as the atomic concentration ratio of Al, the elemental composition is AlxTi 1-xA target material consisting of or containing Al and Ti is selected at a concentration enabling the synthesis of a coating on a substrate placed within a third plasma region, consisting of or containing cubic aluminum nitride with N, and X is 0.8.

[0078] In a more detailed embodiment of the cathode arc deposition apparatus of the present invention, the apparatus has a target (3) having a target surface (3') with an active surface (3'') capable of evaporating the material within a cathode arc process, a confinement part (4) surrounding the outer boundary of the target surface (3'), an anode (2) having an electron receiving surface (2', 2'', 2'''), the anode (2) surrounding at least one of the target (3) and the confinement part (4) at at least one of the axial distances in front of the target plane and the active surface, a magnetic guiding system configured to provide a magnetic field on a target surface that is basically parallel to at least the outer region of the target surface such that the magnetic field lines are parallel to the target surface or inclined with respect to it at an acute angle α, where the active surface (3'') is a system defined within the region of the surface (3') where the magnetic field lines enter the target surface at an acute angle α ≤ 45°, and includes a central axis Z or a central plane Z', both the confinement part (4) and the anode (2) are formed in a closed geometry, both are electrically insulated from each other and from the target, and the minimum distance of the electron receiving surface (2', 2'', 2''') from the active surface (3'') is the radial distance Δr 14 which is the radial distance Δr where the outer boundary of the target surface (3') has a radial distance r1 from the middle of the target and the inner boundary of the electron receiving surface has a radial distance r4 from the middle of the target, 14 and is defined by at least one of the axial distance h1 from the target surface (3') to the upper boundary of the confinement part or the axial distance h2 from the target surface (3') to the lower boundary of the electron receiving surface (2', 2'', 2''').

[0079] In the device of the invention according to any of the preferred embodiments described above, a substantially parallel magnetic field preferably extends from the target active surface (3') at least up to the axial distances (h1, h2) of the confinement section or the electron receiving surface and / or at least extends to a height of 5 to 20 mm on the target surface.

[0080] In region A on the target active surface, the magnetic flux density B A can be set to an intensity of 20 to 500 gauss or more.

[0081] The confinement section can be made of a magnetic or non-magnetic material.

[0082] The radial distance Δr 14 is preferably 5 to 30 mm.

[0083] The radial distance r1 from the center of the device to the outer boundary of the target surface is preferably 40 to 110 mm.

[0084] The radial distances (h1, h2) are preferably 0 to 20 mm.

[0085] The maximum axial distance h3 of the electron receiving surface is preferably 10 ≤ h3 ≤ 50.

[0086] The magnetic guiding system has a pole arranged in front of the center of the rear surface of the target, and at least a central magnet axially aligned therewith, and a circumferential ring magnet having opposite poles in or below the target plane. The ring magnet preferably surrounds the central magnet and at least a part of the target as assumed.

[0087] At least one of the central magnet and the ring magnet is preferably an electromagnet or a permanent magnet.

[0088] The magnetic axis of the ring magnet is preferably inclined away from the central axis Z or the plane Z' in the upward direction.

[0089] In a preferred embodiment, the ring magnet comprises two electromagnetic coils C2 and C3, and the diameter of C3 is larger than the diameter of C2.

[0090] In another preferred embodiment, the magnetic guidance system further comprises a circumferential yoke surrounding the ring magnet, the target and the anode, and the circumferential yoke is made of a magnetizable material.

[0091] The magnetic guidance system further comprises a central limiter disposed inside or around the center of the target surface, and the central limiter is electrically insulated from the target and has a Curie temperature T C >500 °C and is preferably made of a magnetic material.

[0092] In a preferred embodiment, the central limiter protrudes 0 to 20 mm on the target surface or with respect to the axial distances h1 or h2.

[0093] In another preferred embodiment, the central limiter is in the same plane as the target surface.

[0094] In a preferred embodiment, the confinement part is made of a non-magnetic material.

[0095] In another preferred embodiment, the minimum distance of the electron receiving surfaces (2’, 2’’, 2’’’) from the active surface (3’) is defined by the radial distance Δr 14 and the axial distances h1 or h2.

[0096] The present invention also relates to a vacuum chamber equipped with the cathode arc evaporation device of the present invention according to any one of the embodiments of the present invention described above.

[0097] The present invention also relates to a method for depositing a coating on a substrate in a vacuum chamber by use of a cathode arc deposition apparatus according to one of claims 1 to 18, wherein the electron trap is established in region A at least directly above the target surface by applying a substantially parallel magnetic field having magnetic field lines entering the target surface at an acute angle α≦45° to at least an outer region of the target surface (3) by use of a magnetic guiding system, thereby forming an active surface (3''), and a cathode arc discharge is initiated and maintained on the active surface, and region A is laterally delimited by a confinement part at a floating potential.

[0098] Region B is preferably formed above region A up to a substantially axial distance h3, which is given by the maximum axial distance of the electron receiving surface from the target surface.

[0099] Region C is formed above regions A and B, the magnetic field is very low or zero, and the atmosphere preferably contains at least one of reactive gas molecules, positively ionized metal ions, and positively ionized reactive metal ions.

[0100] In a preferred embodiment of the method of the present invention described above, the cathode arc discharge is maintained at a discharge voltage between 20 V and 50 V.

[0101] In a preferred embodiment of the method of the present invention, the coating is an AlMeN, AlMeO or AlMeNO compound, where Me represents one or more metals of transition metal groups IV, V or VI.

[0102] The present invention also relates to a method for producing a substrate coated by a deposition process according to any one of the embodiments of the present invention described above.

[0103] In a preferred embodiment, the coated substrate is a tool or a component.

Explanation of reference numerals

[0104] 1 Vacuum chamber 2 Anodes 2’, 2’’, 2’’’ Electron receiving surfaces of the anodes 3 Targets 3’ Target surface 3’’ Target active surface 4 Electron confinement part at the floating potential 4’, 4’’, 4’’’ Inner surfaces of the confinement part 5 Arc discharge supply 6 Cooling channel anode 7 (Biased / unbiased) substrate 8, 8’ Magnetic field lines with respect to the anode 9 Magnetic field lines with respect to the confinement part 10 Gas plasma 11 Gas inlet (N2, O2, CH4, C2H2, Ar) 12 Target back plate 13 Cooling channel back plate 14 Central magnet 15 Ring magnet 16 Electrically floating strong magnetic central limiter 17 Ground potential strong magnetic peripheral yoke 18 Central coil yoke 19 Insulating device for the central limiter 20 Insulating device for the confinement part 21 Outer coil yoke 22 Seal 23 Electrical insulating device for the target 24 Anode base 25 Anode extension 26 Part of the chamber, or components within the chamber or on the chamber, e.g., flange or part of the flange preferably electrically connected to the anode so as to have the same potential C1, C2, C3 Electromagnetic coils 1, 2, 3 h1 Axial distance from the active surface 3’ to the upper boundary of the confinement part 4 h2 Axial distance from the active surface 3’ to the lower boundary of the electron receiving surfaces 2’, 2’’, 2’’’, which can be the same as h1, as shown in the left - hand electron receiving surfaces 2’, 2’’ in Fig. 2 Axial distance from the active surface 3' to the upper boundary of the h3 electron receiving surfaces 2', 2'', 2''' M Magnetic axis r1 Radial distance from the central axis to the circular target 3, or radial distance from the central plane to the polygonal, for example, rectangular target 3 r2 Radial distance from the central axis / plane to the inner diameter / boundary of the confinement part 4 r3 Radial distance from the central axis / plane to the outer diameter / boundary of the confinement part 4 r4 Radial distance from the central axis / plane to the inner diameter / boundary of the electron receiving surfaces 2', 2'', 2''' r5 Radial distance from the central axis / plane to the outer diameter / boundary of the electron receiving surfaces 2', 2'', 2''' r6 Radial distance from the central axis / plane to the outer boundary of the arc source Z Central plane or axis for each circular target of the polygon

Claims

1. A planar target (3) as a cathode having a target front surface (3') with a target active surface (3'') where magnetic field lines enter the target surface at an acute angle α ≦ 45°, a target rear surface facing a target rear plate (12) that is parallel to the target front surface and disposed on the side facing the target front surface, and a target side surface connecting the target front surface to the target rear surface, A confinement part (4) having an inner surface and an outer surface and disposed adjacent to the target side surface, wherein the target side surface is closer to the inner surface of the confinement part than to the outer surface of the confinement part, the confinement part, An electrode as an anode (2) having inner surfaces (2', 2'', 2''') for serving as an electron receiving surface, A magnetic guiding system configured to provide a magnetic field having magnetic field lines (8, 8', 9) located in front of the target front surface, A cathode arc evaporation apparatus comprising: The inner surface of the confinement part (4) is disposed between the target front surface and the electron receiving surface (2', 2'', 2''') of the anode (2) with respect to the distance from the vertical plane to the target front surface, and / or is disposed between the target side surface and the electron receiving surface of the anode with respect to the distance from the parallel plane to the target front surface, The magnetic guiding system is designed and adjusted to generate at least two magnetic field regions, a first region having magnetic field lines (9) that emerge from the target front surface (3') and terminate at the inner surface (4', 4'', 4''') of the confinement member (4) and are located in front of the target front surface, and a second region having magnetic field lines (8, 8') that emerge from the target front surface (3') and terminate at the electron receiving surface (2', 2'', 2''') of the anode (2) and are located in front of the target front surface, The magnetic guiding system includes at least a central magnet (14) having a pole located in front of the center of the target rear surface and axially aligned with the pole, and a circumferential ring magnet (15) having inter-poles inside or below the target plane, the circumferential ring magnet surrounding at least a part of the central magnet and the target, The magnetic guiding system further includes a circumferential yoke (17) surrounding the circumferential ring magnet, the target, and the anode, the circumferential yoke being made of a magnetizable material, the apparatus.

2. The apparatus according to claim 1, comprising a strong magnetic center limiter (16) disposed within or around the center of the target surface (3', 3''), the strong magnetic center limiter (16) being electrically floating to change the trajectory of the magnetic field lines emerging from the target front surface so as to be parallel to the plane of the target front surface.

3. A planar target (3) having a target surface (3') with a target active surface (3'') capable of evaporating material within a cathode arc process, A confinement part (4) surrounding the outer boundary of the target surface (3'), An anode (2) having an inner electron receiving surface (2', 2'', 2'''), the anode (2) surrounding at least one of the target (3) and the confinement part (4) at at least one of the axial distances in front of the target plane and the active surface. A magnetic guiding system configured to provide a magnetic field on the target surface parallel to at least the outer region of the target surface, or inclined to this at an acute angle α, such that the magnetic field lines are parallel to the target surface or enter the target surface at an acute angle α ≦ 45°, wherein the active surface (3'') is defined within the surface (3') region such that the magnetic field lines enter the target surface at an acute angle α ≦ 45°. A central axis Z or a central plane Z', A cathode arc deposition apparatus comprising Both the confinement part (4) and the anode (2) are formed in a closed geometry and are both electrically insulated from each other and from the target. The minimum distance of the electron receiving surfaces (2', 2'', 2''') from the active surface (3'') is the radial distance Δr of the outer boundary of the target surface (3') to the inner boundary of the electron receiving surface. １４ The outer boundary of the target surface (3') has a radial distance r1 from the central axis Z or the central plane Z' of the target, and the inner boundary of the electron receiving surface has a radial distance r4 from the central axis Z or the central plane Z' of the target. The radial distance Δr １４ is defined by at least one of the axial distance h1 from the target surface (3') to the upper boundary of the confinement part and the axial distance h2 from the target surface (3') to the lower boundary of the electron receiving surfaces (2', 2'', 2'''). The magnetic guiding system comprises at least a central magnet (14) having a pole located in front of the center of the target rear surface and axially aligned with the pole, and a circumferential ring magnet (15) having mutually opposite poles within or below the target plane, the circumferential ring magnet surrounding at least a part of the central magnet and the target. The apparatus, wherein the magnetic guiding system further comprises a circumferential yoke (17) surrounding the circumferential ring magnet, the target, and the anode, the circumferential yoke being made of a magnetizable material.

4. The apparatus according to claim 2 or 3, characterized in that a parallel magnetic field extends from the target surface (3') at least up to the axial distances (h1, h2) of the confinement part or the electron receiving surface, and / or extends at least to a height of 5 to 20 mm on the target surface.

5. In region A on the target active surface, the magnetic flux density B Ａ is set to a strength of 20 to 500 gauss or more, Said region A is laterally delimited by a confinement part at a floating potential surrounding said target, and by an inactive surface region of the target where magnetic field lines enter the target surface at an angle > 45° with respect to the center of the target, or by a central limiter. The device according to any one of claims 1 to 4, wherein said region A is axially separated from said target by the last magnetic field line (9) entering the confinement part at the upper boundary of the confinement part. **Claim 6** The device according to any one of claims 1 to 5, characterized in that at least one of said central magnet and said peripheral ring magnet is an electromagnet or a permanent magnet. **Claim 7** The device according to any one of claims 1 to 6, characterized in that the magnetic axis of said peripheral ring magnet is inclined away from the central axis Z or the plane Z' in the upward direction. **Claim 8** The device according to any one of claims 1 to 7, characterized in that said peripheral ring magnet comprises two electromagnetic coils C2 and C3, and the diameter of C3 is larger than the diameter of C2. **Claim 9** The magnetic guidance system further comprises a central limiter disposed within or around the center of the target surface, the central limiter being electrically insulated from the target and made of a magnetic material having a Curie temperature T Ｃ >500 °C, the device according to any one of claims 1 to 8. **Claim 10** Said central limiter is on the target surface, or projects 0 to 20 mm with respect to the axial distance h1 or h2, or is in the same plane as the target surface, for the device according to claim 9. **Claim 11** The device according to any one of claims 1 to 10, characterized in that said confinement part is made of a non-magnetic material. **Claim 12** A vacuum chamber comprising the device according to any one of claims 1 to 11. **Claim 13** A method for depositing a coating on a substrate in the vacuum chamber according to claim 12, using the device according to any one of claims 1 to 11, wherein the magnetic field is set close to and substantially parallel to the target active surface, at least with respect to the outer region of the target active surface. **Claim 14** An electron trap is established at least directly above the target surface in region A by applying a substantially parallel magnetic field with magnetic field lines entering the target surface at an acute angle α ≤ 45° to at least the outer region of the target surface (3) using said magnetic guiding system, whereby an active surface (3'') is formed and a cathode arc discharge is initiated and maintained on the active surface. The region A is laterally delimited by a confinement part on a floating potential surrounding the target, by an inactive surface region of the target where magnetic field lines enter the target surface at an angle > 45° with respect to the center of the target, or by a central limiter, The method according to claim 13, wherein the region A is axially delimited from the target by the last magnetic field line (9) entering the confinement part at the upper boundary of the confinement part.

15. The region B is formed on the region A up to an axial distance h3 given by the maximum axial distance of the electron receiving surface from the target surface, or up to the last magnetic field line (8) entering the electron receiving surface at the highest or outermost boundary of the electron receiving surface, The method according to claim 13 or 14, wherein the average magnetic field strength of the region B is smaller than the average magnetic field strength of the region A.

16. The region C is formed over the regions A and B between the arc source and the surface of the substrate (7) to be coated, the magnetic field being extremely low or zero, and the atmosphere containing reactive gas molecules and further containing at least one of positively ionized metal ions and positively ionized reactive metal ions, the method according to any one of claims 13 to 15.

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